DE19509301A1 - Multiple W / O / W emulsions - Google Patents

Abstract

Stable multiple W/O/W emulsions are obtained by emulsifying an oil phase with an aqueous phase in the presence of an emulsifier mixture that contains (a) polyolpolyhydroxystearates and (b) anionic, non-ionic, cationic, amphoteric and/or zwitterionic surfactants.

Description

Field of the invention

The invention relates to multiple W / O / W emulsions with a Content of Polyolpolyhydroxystearaten and surfactants as Emul gators, a process for their production and the use of tion of mixtures of Polyolpolyhydroxystearaten and Tensi as emulsifiers for the production of multiple W / O / W emulsions sions.

State of the art

Multiple emulsions are emulsions of emulsions. Je after production one differentiates multiple water / oil / water (W / O / W) as well as oil / water / oil (O / W / O) emulsions. The important The application of multiple emulsions consists of otherwise not miscible or confectionery are to process in a recipe. Another advantage is that the active ingredients controlled by a longer period can be released. Multiple Emul Therefore, ions are particularly useful for the production of kosme  tables and pharmaceutical products of particular importance [Cosm. Toil. 105, 65 (1990) and 106, 97 (1991)].

A particularly elegant process for the production of mul Tiplen emulsions is described by S. Matsumoto in J. Coll. Interf. Sci 57, 353 (1976): Hereinafter, at first increases temperature and under high shear a Prae emulsion subsequently prepared at ambient temperature and under low shear in the aqueous solution of a hydro philen emulsifier is introduced. As emulsifier pair is Sorbitan monoleate and polyethylene glycol derivative used.

From the extensive state of the art is also known that as hydrophilic emulsifiers for the production of multiple Emulsions basically monoglycerides, sorbitan esters, poly Sorbate and highly ethoxylated fatty alcohols come into consideration. Representative is here on the publications in Pharm. Acta. Helv. 66, 343 (1991), as well as by Seiller and Luca in Bull. Tech. / Gattefosse Rep. 80, 27 (1987), S.T.P. Pharia 4, 679 (1988) and Int. J. Cosmet. Sci. 13, 1 (1991).

From Yakugaku Zasshi 112, 73 (1992) are also W / O / W Emul known, the Glycerintrifettsäureester as an oil body and hydrophilic polymers, such as gelatin, as Stabilizer included. The use of albumin and polyacrylates as stabilizers for the water phase so as nonionic surfactants for the oil phase is from J. Controlled Release 3, 279 (1986). Such formulations have become however, especially with temperature fluctuations as not sufficiently stable on storage. From the European Pa Patent application EP-A1 0174377 (Meji Milk Products) is further  the concomitant use of Polyglycerinpolyricinoleaten as Emul gators for the production of multiple emulsions. Also However, these emulsions have just in tempera fluctuations have not proved sufficiently stable.

For the production of stable multiple emulsions it is necessary Use of high molecular weight, lipophilic emulsifiers. In an essay by P. Hameyer and K. R. Jenni in Parf. Kosm. 75, 12, 842, for example, the use of Cetyl Dimethi cone copolyols described. Because of the proportion of polyoxy ethylene groups, this group of emulsifiers for the A however, in lately cosmetic products recently controversial. Also from a publication of K. Stickdorn et al. in perfume Kosm. 75, 904 (1994) are Verfah ren known for the production of multiple emulsions. Here in Both are two-step process with hydrophilic, ethylene oxide-containing emulsifiers in the secondary emulsion as well one-step procedures using only EO-containing emulsifiers described for the above ge concerns may also apply.

The object of the invention has thus consisted in a Step stable, even against temperature fluctuations be to provide continuous multiple W / O / W emulsions, the one from an application point of view towards Cetyl Di Methicone copolyols at least equivalent lipophilic Emulsifier with, however, improved skin-cosmetic properties included. Furthermore, the emulsions should like As free as possible from hydrophilic, ethylene oxide-containing co-emulsa be gates.  

Description of the invention

The invention relates to multiple W / O / W emulsions, the This is obtained by adding an oil phase in the presence of a Emulsifier mixture containing

• (a) Polyol polyhydroxystearates and
• (b) anionic, nonionic, cationic, amphoteric and / or or zwitterionic surfactants

emulsified with a water phase.

Surprisingly, it was found that Polyolpolyhy droxystearate in general and polyglycerol polyhydroxy Stearates in particular in combination with ethylene oxide-free Surfactants as effective lipophilic emulsifiers for single-stage Production of multiple W / O / W emulsions are suitable and thus from an application point of view at least gleichwerti substitute for ethylene oxide-containing cetyl dimethicone copolyols group; at the same time, the ethylene oxide-free polyol polyhydroxystearates together with surfactant co-emulsifiers significantly better skin-cosmetic properties.

polyolpolyhydroxystearates

The in the context of the invention as emulsifiers for the manufacturer ment of multiple W / O / W emulsions eligible Polyolpolyhydroxystearates are known substances which one after the relevant procedures of the preparative orga can obtain niche chemistry. For their production can at  For example, polyhydroxystearic acid with a self-condensing tion degree in the range of 2 to 20, preferably 2 to 10, with Esterify polyols in a conventional manner.

The polyol polyhydroxystearates can be derived from polyols th which at least two, preferably 3 to 12 and ins particular 3 to 8 hydroxyl groups and 2 to 12 carbon atoms. Typical examples are glycerol, alkylene cole such as ethylene glycol, diethylene glycol, Pro pylenglycol; polyglycerol; Methyolverbindungen, in particular trimethylolethane, trimethylolpropane, trimethylolbutane, Pentaerythritol and dipentaerythritol; Alkylglucosides with 1 to 22, preferably 1 to 8 and especially 1 to 4 carbons in the alkyl radical such as methyl and Butylglu Cosid; Sugar alcohols with 5 to 12 carbon atoms such as For example, sorbitol or mannitol, sugar with 5 to 12 Koh lenstoffatomen such as glucose or sucrose; or amino sugars such as glucamine.

In a preferred embodiment are used as emulsifiers Used polyglycerol polyhydroxystearates which are obtained by adding polyhydroxystearic acid with an autocondensate tion degree in the range of 2 to 20, preferably 2 to 10, with a polyglycerine mixture of the composition (GC method)

glycerin 5 to 35 (15 to 30)% by weight diglycerols 15 to 40 (20 to 32)% by weight triglycerols 10 to 35 (15 to 25)% by weight tetraglycerols 5 to 20 (8 to 15)% by weight Penta Glycerine 2 to 10 (3 to 8)% by weight

(Oligoglycerine ad 100 wt .-%) in a conventional manner esterified; in brackets are the preferred range che.

The preparation of Polyolpolyhydroxystearate can in itself done in a known manner. In the case of Polyglycerinpolyhy droxystearate is preferably initially the polyglyce and then the polyhydroxystearic acid produced and finally both esterified.

The preparation of a polyglycerol of the above-mentioned Composition can by self-condensation of glycerol in Presence of suitable catalysts such as Potassium carbonate, silicates according to DE-A1 40 29 323 (Henkel) or Borates according to DE-A1 41 17 033 (Henkel) at temperatures in Be rich be carried out from 200 to 260 ° C.

The preparation of polyhydroxystearic acid takes place at For example, by alkaline-catalyzed polycondensation of Hydroxystearic acid, preferably 12-hydroxystearic acid, the by curing ricinoleic acid or technical castor oil fatty acid is obtained. Preferably, linear Esterification products with 2 to 10 and in particular 2 to 8 Formed fatty acid units. Typically, the following will be Distribution (GPC method) achieved:

monomers 1 to 10% by weight dimers 5 to 15% by weight trimers 5 to 15% by weight tetramers 5 to 15% by weight pentamers 5 to 15% by weight   hexamers 5 to 15% by weight heptamer 5 to 15% by weight octamers 1 to 10% by weight oligomers ad 100% by weight

In a particular embodiment of the invention, Ge Mix of hydroxystearic acid and ricinoleic acid or techni ricinus oil fatty acid containing about 90% by weight of ricinol acid in the weight ratio 90: 10 to 50: 50 and preferably 75: 25 to 60: 40 used. In the same Wei se, it is possible to condense the acids individually and then mix the condensates.

In the subsequent condensation of the polyol, at For example, the polyglycerol with the polyhydroxystearic acid or mixtures with polyricinoleic acid, becomes a complex Mixture of homologous polyester formed. The proportions of mono, Di-, tri- and oligoesters in the polyol according to the invention lyhydroxystearates and preferably polyglycerol polyhydroxy Stearaten depends on the conditions of use of the Aus starting compounds. In a preferred embodiment of Invention is an emulsifier with particularly advantageous applied technical properties that you get by adding about 1000 kg of 12-hydroxystearic acid as long as one Self-condensation until a product with an acid number ranges from 50 to 55, and then this with about 150 kg of polyglycerol the above together further esterified until the acid number drops to one Value less than 2 has decreased.  

Surfactant co-emulsifiers

The selection of surfactant co-emulsifiers is not very critical, since it is to carry out the one-stage Herstellver driving only the emulsifier and a second, to a large extent requires any surfactant component.

Typical examples of anionic surfactants are alkylbenzene sulfonates, alkanesulfonates, olefinsulfonates, alkylethersul fonates, glycerol ether sulfonates, α-methyl ester sulfonates, Sul fatty acids, alkyl sulfates, fatty alcohol ether sulfates, glyce amine ether sulfates, hydroxymethylene ether sulfates, monoglyceride (ether) sulfate, fatty acid amide (ether) sulfate, mono- and dial Kylsulfosuccinate, mono- and dialkylsulfosuccinamates, sulfo triglycerides, amide soaps, ether carboxylic acids and their salts, Fatty acid isethionates, fatty acid sarcosinates, fatty acid taurides, Acyl lactylates, acyl glutamates, acyl tartrates, alkyl oligogluco sidsulfate, protein fatty acid condensates (especially plant wheat-based products) and alkyl (ether) phosphates. If the anionic surfactants Polyglycoletherketten enthal they can be conventional, but preferably one have narrow homolog distribution.

Typical examples of nonionic surfactants are fatty alcohol holpolyglycol ethers, alkylphenol polyglycol ethers, fatty acid po lyglycol esters, fatty acid amide polyglycol ethers, fatty amine polyglycols colether, alkoxylated triglycerides, partial glyceride esters, Mixed ethers or mixed formals, alk (en) yloligoglycosides, fat acid N-alkylglucamides, polyol fatty acid esters, sugar esters, Sorbitan esters and polysorbates. Unless the nonionic Surfactants contain polyglycol ether chains, they can be one  conventional, but preferably a narrow homolo have gene distribution.

Typical examples of cationic surfactants are quaternary amines monium compounds and esterquats, in particular quaternized Fettsäuretrialkanolaminester salts.

Typical examples of amphoteric or zwitterionic surfactants are alkylbetaines, alkylamidobetaines, aminopropionates, amino glycinates, imidazolinium betaines and sulfobetaines.

The surfactants mentioned are exclusively known compounds. Regarding structure and production these substances are included in relevant reviews For example, J. Falbe (ed.), "Surfactants in Consumer Pro ducts ", Springer Verlag, Berlin, 1987, pp. 54-124 or J. Falbe (ed.), "Catalysts, Surfactants and Mineral Oil Additives", Thieme Verlag, Stuttgart, 1978, pp. 123-217.

In view of the fact that the emulsifier mixture free of ethylene lenoxidbausteinen should be, but also because of the superior application properties is the use of ten preference is given to sidic co-emulsifiers which are selected from the group formed by sulfosuccinates, ethercar fatty acids, fatty acid isethionates, fatty acid taurides, fatty acids resarcosinates, monoglyceride (ether) sulfates, alkyl oligogluco siden, fatty acid N-alkylglucamiden, Betaintensiden and / or Protein fatty acid condensates.  

The weight ratio between the polyhydroxystearates and The surfactant co-emulsifiers can 1: 1 to 1: 20 and preferably 1:10 to 1:15.

oil phase

The oil phase can in addition to oil bodies and other co-emulsifiers especially fats, waxes, stabilizers and overfat contained.

For example, Guerbet alcohols are based on oil of fatty alcohols containing 6 to 18, preferably 8 to 10, Koh lenstoffatomen, esters of linear C₆-C₂₀ fatty acids with li near-C₆-C₂₀-fatty alcohols, esters of branched C₆-C₁₃- Carboxylic acids with linear C₆-C₁₈ fatty alcohols, esters of li near C₆-C₁₈ fatty acids with branched alcohols, in particular 2-ethylhexanol, esters of linear and / or branched Fatty acids with polyhydric alcohols and / or Guerbetalkoho len, triglycerides based on C₆-C₁₀ fatty acids, vegetable Oils, branched primary alcohols, substituted cyclohexanes, Guerbet carbonates and / or dialkyl ethers.

Other co-emulsifiers include both known W / O as also O / W emulsifiers such as Polyglycerinfettsäu ester or glycerol fatty acid ester in question.

Typical examples of fats are glycerides, as waxes kom Menu. a. Beeswax, paraffin wax or microwaxes if appropriate in combination with hydrophilic waxes, for. Cetyl stearyl alcohol in question.  

As stabilizers metal salts of fatty acids such. B. Magnesium, aluminum and / or zinc stearate used the.

As Überfettungsmittel substances such as polyethoxylated lanolin derivatives, lecithin derivatives, polyol fatty acid esters, monoglycerides and fatty acid alkanolamides ver be used, the latter if necessary gleichzei tig serve as foam stabilizers.

water phase

The water phase can in addition to 50 to 85 wt .-% water still Po lyols such as preferably glycerol and electrolyte salts such as Common salt, ammonium chloride or magnesium sulfate. Other important ingredients Polyitere or thickening be medium. Typical examples are Polysac charide, especially xanthan gum, guar guar, agar-agar, Alginates and tyloses, carboxymethylcellulose and hydroxy ethylcellulose, and also higher molecular weight polyethylene glycol mono- and diesters of fatty acids, polyacrylates, polyvinyl alcohol and polyvinylpyrrolidone. Finally, you can also conserve such as phenoxyethanol, formaldehyde solution, parabens, pentanediol or sorbic acid.  

Preparation of multiple emulsions

Another object of the invention is a method for Producing multiple W / O / W emulsions that require an oil phase in the presence of an emulsifier mixture containing

• (a) Polyol polyhydroxystearates and
• (b) anionic, nonionic, cationic, amphoteric and / or or zwitterionic surfactants

emulsified with a water phase.

To produce the multiple W / O / W emulsion is vorzugswei se the oil phase together with the emulsifier - so the mixture from Polyolpolyhydroxystearat and preferably Polyglycerinpo Lyhydroxystearat with a surfactant co-emulsifier - at Homogenized room temperature and in the likewise homgeni stirred water phase stirred. Preferably, the Emul gator mixtures in amounts of 1 to 10 and in particular 2 to 4 wt .-% - based on the multiple W / O / W emulsion - turned puts. The weight ratio between oil phase and water phase It can range from 50:50 to 10:90 and preferably 20: 80 to 30: 70 are. In conclusion, it may be beneficial be the multiple emulsion by adding, for example, from Alkali metal hydroxide to a skin pH in the range of 5 to adjust to 6.

In principle, the preparation of the emulsions but also by cold, hot, hot-hot / cold or PIT emulsification er consequences. This is a purely mechanical method a chemical reaction does not take place.  

Industrial Applicability

The multiple W / O / W emulsions according to the invention are characterized especially by a special stability fluctuating temperatures. Another object of the The invention therefore relates to the use of mixtures of Polyol polyhydroxystearates and surfactants in general and Polyglycerol polyhydroxystearates and ethylene oxide-free not ionic, ionic or ampholytic surfactants in particular their emulsifiers for single-stage production of multi plen W / O / W emulsions in which they in amounts of 0.1 to 10, preferably 0.2 to 4 wt .-% - based on the multiple Emulsions - may be included.

The multiple W / O / W emulsions in turn can be used for Her production of cosmetic and pharmaceutical preparations such as creams, ointments and lotions used become.

The following examples are intended to form the subject of the invention explain it in more detail without restricting it to it.

Examples Example 1

An oil phase consisting of

10.0% by weight of octyl stearate (Cetiol® 868),
3.0% by weight almond oil,
2.0% by weight of paraffin oil, viscous
2.0% by weight of cyclomethicone (Dow Corning 344)
0.2 wt .-% polyglyceryl-2 polyhydroxystearates (Dehymuls® PGPH) and
2.8% by weight of Potassium Cocoyl Hydrolyzed Collagen (Lamepon® S)

was stirred homogeneously at 22 ° C. Next to it was a water phase consisting of 74.5% by weight of water, 5.0% by weight of glycerol, 0.3 wt.% Carbomer (Carbopol® 981), 0.1 wt.% Xanthan gum (Keltrol®) and 0.12 wt .-% formaldehyde solution also at Homogenized room temperature, with stirring slowly to the Added oil phase and emulsified for 5 min. The resulting mul The final W / O / W emulsion was finally used to adjust the pH to 6.5 with 0.01 wt .-% potassium hydroxide.  

example 2

Example 1 was repeated but as the oil phase a mixture out

14.0% by weight of coco-caprylate / caprate (Cetiol® LC),
2.5% by weight of dicapryl ether (Cetiol® OE),
0.6 wt .-% polyglyceryl-2 polyhydroxystearates (Dehymuls® PGPH) and
2.9 wt% Sodium Cocoyl Hydrolyzed Wheat protein (Gluadin® WIC)

used.

example 3

Example 1 was repeated but as the oil phase a mixture out

9.0% by weight of Decyl Oleate (Cetiol® V),
8.0% by weight of dioctylcyclohexane (Cetiol® S),
0.2 wt .-% polyglyceryl-2 polyhydroxystearates (Dehymuls® PGPH) and
2.8% by weight PEG-20 glyceryl laurate (Lamacit® GML 20)

used.

Claims (11)

1. Multiple W / O / W emulsions obtainable by maintaining an oil phase in the presence of an emulsifier mixture, ent

• (a) Polyol polyhydroxystearates and
• (b) anionic, nonionic, cationic, amphoteric and / or zwitterionic surfactants

emulsified with a water phase. 2. Multiple W / O / W emulsions according to claim 1, characterized ge indicates that they are polyglycerol polyalcohols as emulsifiers hydroxystearates. 3. Multiple W / O / W emulsions according to claims 1 and 2, characterized in that it surfactant co-emulsified contain selected from the group that is formed by sulfosuccinates, ether carboxylic acids, Fatty acid isethionates, fatty acid taurides, fatty acid ars cosinates, monoglyceride (ether) sulfates, alkyl oligogluco siden, fatty acid N-alkyl glucamides, betaine surfactants and / or protein fatty acid condensates. 4. Multiple emulsions according to claims 1 to 3, characterized characterized in that they are the mixtures of polyhydroxy stearates and the surfactant co-emulsifiers in Ge weight ratio 1: 1 to 1: 20 included.   5. Multiple W / O / W emulsions according to claims 1 to 4, characterized in that as oil phase oil body, Fats, waxes, stabilizers and / or superfatting agents tel included. 6. A process for the preparation of multiple W / O / W emulsions, comprising mixing an oil phase in the presence of an emulsifier containing

• (a) Polyol polyhydroxystearates and
• (b) anionic, nonionic, cationic, amphoteric and / or zwitterionic surfactants

emulsified with a water phase. 7. The method according to claim 6, characterized in that the emulsifier mixtures in amounts of 1 to 10 Wt .-% - based on the multiple W / O / W emulsion - a puts. 8. Process according to claims 6 and 7, characterized marked records that the oil phase and the water phase in Weight ratio 50: 50 to 10: 90 used. 9. Use of mixtures of Polyolpolyhydroxystearaten and anionic, nonionic, cationic, amphoteric ren and / or zwitterionic surfactants as emulsifiers for the production of multiple W / O / W emulsions.